gag rule vs rules of order

gag rule and rules of order both are nouns.

Word	Noun	Adjective	Verb	Adverb
gag rule	Yes	No	No	No
rules of order	Yes	No	No	No

As nouns, rules of order is a hypernym of gag rule; that is, rules of order is a word with a broader meaning than gag rule:

Other hypernyms of gag rule include order, parliamentary law, parliamentary procedure.

gag rule (noun)	rules of order (noun)
a rule for limiting or ending debate in a deliberative body	a body of rules followed by an assembly